Be careful, you are loosing your guarantee!
Everytime use your own original Bios for modding!
If the flashing is going wrong and you have a black screen, you can use a pci-graphic card for flashing the GTX280 again or keep the steps in mind and blind-type the commands!

If You cant read out the Bios of your card with Nibitor, use GPU-Z and save the file then open it with nibitor.

Change the "EXTRA" voltage (in the pic below) from 1.18v down to 1.06v and save the file. I recommend to use 1.06v cause 1.03v could not be good in overclocking the card. With 1.03v the system freezes over 665MHz.
The "3D" clock ist 1.06v at stock, you can set it down to 1.03v.

Anytime, if you´re getting freezes, raise the EXTRA voltage from 1.03v to 1.06v for example.

Save nvflash.exe, the original and modded biosfile on the dos-start-disk and boot from the floppy disk.
Type during the dos screen "nvflash.exe -5 -6 biosfile.rom" - confirm with "y" and the flashing is done.

With my Point of View GTX280@ 1.03v, only 655/1410/2430 are stable instead of 700MHz with 1.18v, but its much cooler and more quiet.

I need only 320W at maximum, witch was 380W bevore flashing, thats incredible.

Test (25° celsius room temperature)

30min Furmark
GTX280 - 1.18v
88° - 100% fan

GTX280 – 1.03v
78° - 61% fan (down to 68° Grad with 100%)

1h Crysis
GTX280 - 1.18v
~82° - ~80% Lüfter

GTX280 – 1.03v
~72° - ~51% Lüfter

It doesnt matter which game, the fan is not faster than 1080rpm/61%!! In Crysis, Age of Conan, Assassins Creed, Jericho the Fan is mostly about 50%, 72-76°, and ~280W, thats amazing!

The Card is absolutely silent in 2D with the Fan at 25%. Rivatuner is managing the Fan by itself and only if the GPU Temp is getting over 65° celsius the fan ist moving from 25% to auto. (you have to create oc and fan profiles in rivatuner!)
In idle, the GPU is about 55° celsius and 25% fan (25° room temperature)

OC with less Volt? SURE!!

With 1.03v under load, i can manage 655/1410/2430

I played Crysis, Age of Conan, Assassins Creed, Jericho for about 12h and the card was absolutely stabel, even in Benchmarks (3Dmark/Furmark)

Be careful, you are loosing your guarantee!
Everytime use your own original Bios for modding!
If the flashing is going wrong and you have a black screen, you can use a pci-graphic card for flashing the GTX280 again or keep the steps in mind and blind-type the commands!

If You cant read out the Bios of your card with Nibitor, use GPU-Z and save the file then open it with nibitor.

Change the "EXTRA" voltage (in the pic below) from 1.18v down to 1.06v and save the file. I recommend to use 1.06v cause 1.03v could not be good in overclocking the card. With 1.03v the system freezes over 665MHz.
The "3D" clock ist 1.06v at stock, you can set it down to 1.03v.

Anytime, if you´re getting freezes, raise the EXTRA voltage from 1.03v to 1.06v for example.

Save nvflash.exe, the original and modded biosfile on the dos-start-disk and boot from the floppy disk.
Type during the dos screen "nvflash.exe -5 -6 biosfile.rom" - confirm with "y" and the flashing is done.

With my Point of View GTX280@ 1.03v, only 655/1410/2430 are stable instead of 700MHz with 1.18v, but its much cooler and more quiet.

I need only 320W at maximum, witch was 380W bevore flashing, thats incredible.

Test (25° celsius room temperature)

30min Furmark
GTX280 - 1.18v
88° - 100% fan

GTX280  1.03v
78° - 61% fan (down to 68° Grad with 100%)

1h Crysis
GTX280 - 1.18v
~82° - ~80% Lüfter

GTX280  1.03v
~72° - ~51% Lüfter

It doesnt matter which game, the fan is not faster than 1080rpm/61%!! In Crysis, Age of Conan, Assassins Creed, Jericho the Fan is mostly about 50%, 72-76°, and ~280W, thats amazing!

The Card is absolutely silent in 2D with the Fan at 25%. Rivatuner is managing the Fan by itself and only if the GPU Temp is getting over 65° celsius the fan ist moving from 25% to auto. (you have to create oc and fan profiles in rivatuner!)
In idle, the GPU is about 55° celsius and 25% fan (25° room temperature)

OC with less Volt? SURE!!

With 1.03v under load, i can manage 655/1410/2430

I played Crysis, Age of Conan, Assassins Creed, Jericho for about 12h and the card was absolutely stabel, even in Benchmarks (3Dmark/Furmark)

Stay cool!

fantastic idea, I made the change and loaded the new modded bios. Everything works perfectly and now the fan does not exceed 60% in full load! WOW!!!

one question..... if i have problems and i must send my card in assistence, loading the original bios I would be warranted?

fantastic idea, I made the change and loaded the new modded bios. Everything works perfectly and now the fan does not exceed 60% in full load! WOW!!!

one question..... if i have problems and i must send my card in assistence, loading the original bios I would be warranted?

Lol! Are you serious?

Cause the 80%-100% Fan is annoying!

I know about 30 people who own a GTX280 and 10 are getting a watercooler for the GTX280 and 10 are flashing their bios.
What you do is your choice - my choice is the silence (less heat, less power consumption)

I know about 30 people who own a GTX280 and 10 are getting a watercooler for the GTX280 and 10 are flashing their bios.
What you do is your choice - my choice is the silence (less heat, less power consumption)

Undervolting the card is not the way to go, though. If you undervolt it, then when the card is under full load and needs that extra voltage and can't find it, then it's going to either fizzle out or die. Perhaps both.

There's an easier solution for a buzzing fan. It's called "case airflow." Either get a case that has vents on the side or buy a couple of high CFM fans to place around the card to suck in cool air through. Voila. The extra loud fan on the card won't have to spin as fast because the temps inside the case won't be like a sahara desert.

But no one should undervolt their video card; that's just asking for trouble. If the voltage is set at spec, it's because the card will eventually need it to perform. I'm always amused by forum gurus who think they know more than MIT engineers up at Nvidia.

Undervolting the card is not the way to go, though. If you undervolt it, then when the card is under full load and needs that extra voltage and can't find it, then it's going to either fizzle out or die. Perhaps both.

There's an easier solution for a buzzing fan. It's called "case airflow." Either get a case that has vents on the side or buy a couple of high CFM fans to place around the card to suck in cool air through. Voila. The extra loud fan on the card won't have to spin as fast because the temps inside the case won't be like a sahara desert.

But no one should undervolt their video card; that's just asking for trouble. If the voltage is set at spec, it's because the card will eventually need it to perform. I'm always amused by forum gurus who think they know more than MIT engineers up at Nvidia.

QFT.

The people who designed the card didn't pull the stock voltage number out of thin air. They rigorously tested the card to make sure it was perform correctly without errors. The card may run with a lower voltage, but it will likely have worse performance and causing more issues such as BSODs or display driver stopped responding.